1. Field of the Invention
This invention relates to a nest type pressure connecting device suitable to be used for contacting an electric part such as leadless IC or the like which has a number of conductive pads (terminals) on its lower surface.
2. Brief Description of the Prior Art
A conventional pressure connecting device of this type, as disclosed in Japanese Utility Model Early Laid-open Publication No. Sho 63-25467, includes an outer jacket member having a stationary terminal, a coil spring and a movable terminal to be inserted into one end of an opening of the outer jacket member such that the movable terminal is resiliently held by the coil spring, the end of the opening in the outer jacket member being, by way of example, reduced inwardly in order to prevent the coil spring and movable terminal from escaping therefrom, an inner bottom portion of the outer jacket member and an inner end portion of the movable terminal being provided with a recess portion, respectively, the end portion of the coil spring being inserted into and supported by both the recess portions, whereby the movable terminal is pushed down by the electric pads of an electric part to compress the coil spring, so that the movable terminal is elastically caused to contact the conductive pad of the electric part by a bias of the coil spring.
The pressure connecting device thus constructed has such problems that a coil spring must be prepared as a separate part in addition to an outer jacket member and an inner jacket member, and therefore, the number of component parts required is increased, thus resulting in high cost.
Furthermore, a bias is generated to the coil spring to incline the movable terminal when an electric part is mounted, with the results that the contact pressure is not uniform and the sliding movement of the movable terminal in the axial direction is not smooth. Moreover, the repeated use of the coil spring is likely to deteriorate its elasticity.